You have a hard time remembering an age when you didn't DVR shows to watch later. But that's never been true for the majority of Americans—until now. The time-shifters are taking over. And it's wonderful.

The news comes from a Comcast survey of 1,000 television viewers—in and out of their network—in which a full 62% of respondents said they'd watched a TV show at a time other than it was originally broadcast (called time-shifting). That includes both DVR and on-demand viewings, and could foreshadow the end of prime time as we know it.

Here's the general idea: the more people access their favorite shows at a time other than its original airing, the less reason there is to have an "original" air time at all. The schedule could instead become fully on-demand, with ads targeted based on when and even where you're watching a given show. It'll be even more feasible if and when the internet-enabled TV boom happens.

So why wouldn't it happen? For one thing, it's hard to find an industry more entrenched in a business model than than television broadcasting. For another, it discounts the still powerful notion of appointment television; shows like Mad Men or, when it was on, Lost, don't necessarily demand live viewing, but they're events that people schedule their nights around.

What's more likely is that your on-demand options will continue to expand to other platforms. We've seen two important instances of that already this week, with HBO Go and live Verizon FiOS TV both coming to the iPad.